>The defendant has the right, but not the obligation to be present. If they're informed of the trial but don't show up or send a representative, the trial can go ahead anyway.
According to the wikipedia article, it's not as simple as that. It's allowed in some european states but not others. In the US it's disallowed with a variety of exceptions, none of which include "accused was too hard to apprehend".
>It would be difficult to try minor crimes (like traffic court) if not turning up to court meant you couldn't be punished.
AFAIK those are civil offenses, not criminal offenses, so you don't get many of the due process protections.